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Discussion Starter · #1 ·
hi guys,

my car feels so slow, im sure there is no boost what so ever. i dunno what it could be, ive changed the maf, and oil so far, with no effect. does anyone have any suggestions? i cant stand this no more! everyone elses 1.8t feels lightning quick compaired to my piece of crap!

also recently the car has been back firing alot between gear changes, and idle is erratic, the revs just bounce up and down really quickly until it stalls. i turned on the rear window de misters the other day and the car went siko and cut out!

thanks
 

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christ! that sounds like a nightmare...sounds like an electrical problem dude, best of taking it to a garage and letting em hook it up to a machine to see where the hiccup is...
 

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hi mate. there is sooo much on these engines that itcould be and it could be something so simple.1st things1st get itto a local vw specialist and huck it up to VAG COM that will/should tell you whats wrong.....i had this prob and found 3 things wrong my MAF AGAIN,air flow amplifier and a boost control unit or something?140 later it felt like a new car..

good luck mate

gray
 

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I would hook it up to VAG COM first to see if you have any errors..  The idling problem sounds like a throttle body clogged up.  I would Try cleaning that out first you probably find there is loads of crap in there...  Do a search on the forum there is over 100 posts on how to do it....  Also when you put your new MAF off did you disconnect the battery for 15-20 mins and then change it...  After connecting the battery back up you supposed to start the car and let it run idle for 5 mins so that the ECU can reconise the new MAF reading....
 

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Discussion Starter · #5 ·
thanks for the imput u guys, im new to vw's. first time ive owned a car with turbo as well, so not sure what there all about if you know what i mean! ive never had this sort of problem with any of my previous cars. my only knowledge of this car is doing search's on here! good stuff.

cleaning the throttle body sounds like a plan, thanks for the tip.

i didnt follow that procedure when i changed the maf, however it has been a few weeks since it was done, surely the ecu has had time to notice it by now? maybe i should try this as well jus for the heck of it, whilst the throttle gets done.

after trying these out, and it dosent make progress, deffo time for vw garage to take over!
 

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yeh that sounds like a plan. dissconect the battery when you do it all. i think this will reset the ecu if you leave it dissconected for half hour.mite be wrong clean throttle. then when its all fitted again letthe car idle for a bitlet the ecu reconise what you have done.
 

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I had the exact same symptoms. In my case, it WAS the MAF. Maybe you got a faulty MAF?

I didn't disconnect the battery or anything either. I just plugged in the new MAF, and BOOM. Car was lightning quick again ;)

Is there any way at testing if your MAF is faulty? Where did you get it? Suggest to them you beleive the MAF may have been faulty, and ask if you can test with a new one?

P.S. I got my MAF from Autovax. Its a vauxhall specialist, but it was the cheapest I could find a Bosch MAF. ?52 + VAT. Bargain.
 

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Hi ya fella

Like what the others said, give your throttle body a clean, clean the maf, check all your fuses goin to engine componants in the fuse box!

Also do you know if you have an atmospheric dump valve?
 

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Discussion Starter · #9 ·
dam if only i wrote on here before i bought the maf, i got scummed for vw price!

ive got a baileys re circulate dump valve, however ive had this checked and all seemed well with it.

all this recent slow driving is making me feel sick! hopefully once the car has overcome this problem, its deffo getting chipped of some sort, im missing out on the fun! would you guys recommend upsolute?
 

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If you have a baileys recirc valve then how did you test it was ok...  I used to have one of these and so did a couple of members on here and our experiance of these are that they are pants.......  They eventually give up especially if you have a remap.  To test take the Dv out push the piston in with your finger and put another finger on the top of the DV where the small boost pipe goes.  The piston once released should hold if it does not then its had its day and will probably need a service if that is the case you are best getting a forge 007 one....... 
 

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Discussion Starter · #11 ·
now im dubious about the DV now! i remember sticking fingers in and testing the moving bit, dunno about it holding though..... should maybe stick the oem plastic back in? does a faulty DV make the car lose performance?
 

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yeh deffinatly it wont hold boost properly if its knackered, do yourself a favour don't put the standard one back on they really unreliable!

Get yourself a forge recirc they are tried and tested to be the best for our cars!

get linked up to VAG.com and see if aint error codes appear then go from there!
 

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Discussion Starter · #13 ·
a wee update.

ive had it in vag, computer shows up as having a hall sender - g40 fault. the mechanic recommends i change a sensor that sits on the back of the air box. not impressed with the price of it, ?180 ex vat, oh well has to be done.

anyone else heard or experianced this fault? hopefully this sorts the car out.
 

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I think Ivor MK4 turbo had the hall sender go tits up on him, he thought his turbo had given up!

Hope its better when they've fitted the new one fella
 

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Hi ive got the same problem, my 1.8t seem very slow, had it on a vag com, no error codes, had new maf, just had service done, new spark plugs.Still runs slow. well stumped. Although i did find like  metal plate hanging near where airbox should be but i have a carbonio on so who ever had it b4 me left it. i was told i needed to be earthed so it is but still no dofference lol any ideas??
 

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Discussion Starter · #16 ·
mmm i was told it was either the cam shaft position sensor or the air box sensor, but he said the air box one because of the symtoms i mentioned, i aint done any yet, cant be assed too expensive.
 

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Discussion Starter · #18 ·
update for anyone else that will experiance this in future!

finally sorted! after trying the maf, ignition amp, and buying a crank sensor by accident :( what a waste of money!

turned out the route of the problem was the cam position sensor.

just been out for a spin, and my god! what have i been missing out on. forgot what the 1.8t felt like!
 

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Glad you got it sorted out in the end mate happy motoring, its awful when something is not right and you have tried everything to sort it out but nothing you do makes a difference, luckily though there are lots of people on here that can help you when it comes to the 1.8T, my self though, i am TDI lad [:D].
 
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